CN1283243A - Low density resilient webs and method of making such webs - Google Patents

Abstract

A method for making a textured tissue sheet on a conventional tissue making machine using a conventional cylindrical drum dryer creates a product that is remarkably bulky, soft, and wet resilient. A combination of rush transfer and sheet molding with three-dimensional fabrics is combined with the step of web inversion to ensure that the surface of the web which was molded onto a first textured transfer fabric is the surface which is placed against the surface of the cylinder dryer. Web inversion improves machine productivity and enhances physical properties of the web.

Description

Low density resilient webs and production method thereof

Background of the present invention

Present invention relates in general to produce the method for paper products.More particularly, the present invention relates on improved conventional wet press, produce the method for no wadding.

In pulp technology for making paper, the cylinder that usually uses the large-scale steam that is called as the Yankee drier to fill come drying be crushed on described dryer drum lip-deep, remain wet paper.In traditional paper-making industry, wet paper is pressed on the surface of Yankee drier securely.Wet letterweight on described cylinder, has been formed contact closely, so that rapidly heat is imported into this paper.Along with the drying of described paper, formed bonding between described Yankee dryer surface and paper, usually can be owing to the bonding agent that sprayed before contact between described hygrometric state paper and the dryer surface is strengthened.When with creping doctor will, when dry paper scrapes off from described dryer surface, described bonding can the disconnection can form decorative pattern tiny, softness like this on described paper, improve its bulk, and it is bonding to disconnect a lot of fibers, so that improve its pliability, and reduces its hardness.

Traditional creping has some defectives.Because the described scraps of paper be concora crush on Yankee, along with the drying of this paper, can between fiber, forming hydrogen bond with flat, intensive state.Although creping can produce a lot of kinks and distortion on described paper, and increases its bulk, after described wrinkling paper was moistening, described kink and distortion meeting were owing to the expansion of fiber is unclamped.Consequently, described paper tends to recover residing flat form when described hydrogen bond forms.Therefore, wrinkling paper tends to the thickness attenuation after moistening, and along the machine direction lateral expansion; if some part of the fabric of described lateral expansion is restricted; remain dry, perhaps remain on another surface and go up words by surface tension, usually can be wrinkling in this technology.

In addition, wrinkling decorative pattern and the bulk that to give described paper that limited.Less with the improvement that the fabric of the traditional operation production of Yankee such as the height graining of the saturating paper of doing can carry out, described paper is produced on dapple dry fabric.Flat, the intensive structure of the paper on the described Yankee has limited the structure that these goods can obtain greatly after leaving described Yankee.

Can avoid above-mentioned and defective other traditional creping by producing the saturating dried paper that does not have wrinkle.Described paper can be made the three-dimensional structure of expansion, rather than flat and intensive structure, thereby good moistening elasticity is provided.But, well-known, the paper of nothing wrinkle tends to hard usually, and has lacked the pliability of wrinkle-removing product.In addition, the saturating paper of doing is sometimes owing in order to realize that white drying flows through the air-flow of described paper, and forms aperture on this fabric.And most of in the world paper machines use traditional Yankee drier, and the unwilling acceptance of paper manufacturers increases and does the expensive of technology or do relevant higher production cost with saturating thoroughly.

The method of producing no wadding sheet in the past on drum dryer or Yankee drier had comprised already with paper roll on described drier.For example, drum dryer is used to high-quality paper for a long time always.In the conventional rollers drying, described paper is carried by dryer fabric, and described fabric wrapping so that form excellent contact, and prevents that paper from sliding on described drum dryer.Unfortunately, described winding-structure is not suitable for the paper machine that the wrinkling paper machine in modern times is transformed into the nothing wrinkle.In addition, under unruffled situation, described paper may be hard and be had a low inside bulk (having low hole between fiber).In addition, owing to destroyed hot transmission, the high speed operation is impossible.When paper is not that hot conduction can be weakened, and makes rate of drying be subjected to obviously weakening when being pressed into flat form with big pressure on Yankee or drum dryer surface.Another problem that runs under high speed is that paper is taken off and be placed into a difficult problem on the Yankee from fabric, if especially true when particularly described fabric has the decorative pattern of height or three-dimensional structure.Described paper can be connected on the described fabric usually securely, and the process that paper is transferred on the Yankee from this fabric can cause the adhesion of paper or the thing that other undesirable paper destroys or damages.In addition, under commercial speed, it is extremely difficult that the stencil paper that does not have wrinkle is connected on the Yankee surface with the problem of separating from the Yankee surface, as mentioned below.

Existing papermaking process had adopted quick transfer or already to the negative stretch technology of l Water Paper, so that improve elasticity and the pliability of not having wrinkle, non-compression drying paper.But, shift fast, paper matrix is pressed onto on the three dimensional fabric, and the combination of roller drying, particularly can cause producing in practice some problems with the industrial useful unruffled operation of speed the time, these problems were not realized in the past or solved.Specifically, the applicant has found that, when fast the part of most of high elongation of the paper that shifts was carried out drying on being pressed in the Yankee surface, when under wrinkling or unruffled situation this paper being separated, this paper can not be connected Yankee and go up or be retained on the Yankee.Do not having the maximum of problem harm described in the wrinkle operation, because do not using creping doctor to carry out under the situation of good separation, the part of described paper can stick on the described Yankee, but can reduce the quality of paper when carrying out wrinkling operation.The fracture of a large amount of paper is consequently arranged, perhaps obtain having low-intensity, uneven characteristic and the acceptable goods of paper defective.

Therefore, need a kind of papermaking operation that has overcome the above-mentioned problem of on the Yankee drier, carrying out paper matrix system, drying, connection and separating.Specifically, need a kind ofly can be on drum dryer to have the nothing wrinkle of stencil paper of defective of very little paper or the method for slight wrinkling production with industrial useful speed production.The paper of producing with this method preferably has 3D shape, so that produce high apparent bulk, the structure of incompressibility drying, so that produce high bulk (as hereinafter giving a definition) and the pliability of adhering to, and connect and separation period between little destruction so that produce soft absorbent value with high intensity.

The present invention's general introduction

Have found that in wetting into net papermaking the saturating dried device that replaces large-scale costliness with traditional Yankee drier or drum dryer can produce soft, high bulk, dapple, moistening flexible paper.Achieve the above object, need make up some operations with a kind of ad hoc fashion, designing this operation is for needed characteristic being provided and avoiding influencing the key issue of producing decorative pattern high bulk paper in the prior art with the Yankee drier.Described key issue concentrates on the interaction aspect that quick transfer, three dimensional fabric and paper are connected with Yankee.Specifically, have found that, under the operations specific condition, if transferring to first of height three-dimensional structure fast shifts paper on the fabric and directly transfers to and have a kind of like this tendency on the Yankee drier: with at a high speed can fracture or adhesion between separation period from this drier, if described paper is dried to industrial valuable dryness level.But, shift on fabric or the felt, can overcome the problem that described serious obstruction is produced to a great extent if before being placed on Yankee or the drum dryer surface, the paper of the quick transfer on the described three dimensional fabric is transferred to second.Therefore, put upside down on the surface of the orientation relatively dry device of described paper.Described second shifts fabric or felt preferably has and is lower than described first and shifts the fabric roughness, but has three-dimensional to a certain degree on surface texture, so that keep or strengthen the decorative pattern of this paper.

Although for production bulking intensity, stretching and decorative pattern, paper is transferred to three-dimensional first on first support fabric fast, and to shift fabric be necessary, but the applicant never find carry out Yankee when dry particularly under no wrinkle pattern this process can cause serious runnability problems.Someone thinks that described quick transfer process can produce tension force and little compression on wet paper, and wherein fiber had been subjected to rearranging with friction between two kinds of fabrics of friction speed operation and shearing already.Specifically, transfer to fast three-dimensional first shift on the fabric after, as if most of ledge of the relative three dimensional fabric below it of described paper has been subjected to special tension force or stress, makes thin, weak part near most of ledge.If the paper that is positioned on the described three dimensional fabric is crushed on the Yankee subsequently, it can be subjected to the stress of height, and the most of protuberance branch of this paper is pressed on the Yankee the most securely.The described position that firmly compresses can the maximum tension force of experience between separation period from the Yankee at described paper, and might adhere between separation period, rupture or breakage.Specifically, the thin position of shifting the highest part of fabric fast near described three-dimensional be described paper might damaged position between separation period on Yankee or the drum dryer.In dryer surface be crushed between the position of the hygrometric state paper on the Yankee and produce combination, and during overcoming described connection power subsequently, described paper can rupture or reduce its quality when drier separates by surface tension and other chemical force.If described paper is separated from drier wrinkle resistantly, might rupture or the adhesion of paper, and the variety of issue of paper still might take place when wrinkling operation.

In order to obtain the intensity of good maneuverability and paper, the paper of described mould (pressure) system should experience at least more once and shift, transfer to second and shift on the fabric, so that guarantee that the described relatively first the highest part that shifts the described paper of fabric is not to be connected the lip-deep part of described drum dryer the most securely.In a kind of specific embodiments, the ledge of described paper can put into second sunk part that shifts on the fabric after the transfer tasks for the first time fast, and by the second transfer fabric described paper is placed on the drum dryer.Therefore, described paper is put upside down, so that the relative first uppermost one side that shifts fabric becomes the minimum one side that shifts on the fabric second.The paper that shifts can be placed on the drum dryer then, and wrinkling or wrinkle resistant the separation, the possibility that adhesion or fracture occur is very little.Even do not allow the ledge on the described paper aim at second depression that shifts on the fabric, just simply described paper is turned to second and shifts on the fabric and when carrying out roller drying subsequently, just can produce favourable result.

We suppose to overturn by this way described paper, can guarantee that the weakest position (position that the motion of the support fabric of relative rapid movement is stretched or rubs during shifting fast) of described paper is not the position that is connected the most securely on the Yankee.As a result, in the unlikely fracture in position that when dryer surface is separated, is subjected to maximum tension.The disclosed method of this paper can shift fast to paper, is molded on the three dimensional fabric, and dry on the Yankee drier with industrial useful speed.The upset of paper can be finished by second transfer step, is that described paper is deposited on the described dryer surface subsequently.In fact, after described first transition phase, can use the extra transfer step of any odd number number, so that transfer on the extra fabric endless belt, to guarantee to carry out the upset of described paper.

Therefore, in one aspect, the present invention relates to a kind of method of producing paper, may further comprise the steps: a) aqueous suspension with paper fibre is deposited on a kind of forming fabric, so that form hygrometric state paper; B) described hygrometric state paper is dewatered to the denseness that is suitable for quick transfer tasks; C) paper of described dehydration is transferred to fast on the first transfer fabric with 3D shape; D) described paper being transferred to second shifts on the fabric; E) described paper is transferred on the surface of drum dryer; With f) described paper is separated from described drum dryer surface.

On the other hand, the present invention relates to a kind of method of producing paper, may further comprise the steps: a) aqueous suspension with paper fibre is deposited on a kind of forming fabric, so that form elementary paper; B) described wet paper is dewatered to about 20% or higher denseness; C) paper of described dehydration is transferred to fast on the first transfer fabric with 3D shape, this shifts the fabric roughness of the fabric roughness of fabric greater than described forming fabric; D) described paper is transferred on the second transfer fabric with the fabric roughness that is lower than the described first transfer fabric; E) described paper is shifted fabric from second and transfer on the surface of drum dryer, and apply the pressure that is suitable for keeping the tangible 3D shape on the described paper; F) dry described paper; With g) described paper is separated from described drum dryer surface.

In a kind of specific embodiments, described paper is shifted fabric from first simply transfer to second and shift on the fabric, send first then again back to and shift fabric, and be lower than relatively and shift fabric and reorientate.As a result, the weakest, the highest part of above-mentioned described paper preferably faces toward or moves to the lower position of described fabric after shifting fast, so that above-mentioned outstanding tension force position can not become the main binding site with drum dryer.Even do not shift on the fabric described paper is not relocated accurately described first, described paper is shifted that fabric transfers and sends it back to first and shift fabric and preferably can the fiber on the described paper be rearranged from first, so that improve roller drying subsequently, and be reduced in the possibility of fracture when separating.In addition, the described paper and first first time of shifting fabric divide defection to reduce fabric winding degree, and reduce when it is placed on the drum dryer once more problem with the adhesion when first shifts the fabric separation of described paper, weaken the possibility of the problem on described drier thus.

" said drum dryer " is the drum dryer of heating, has impermeable basically outer surface, and being applicable to by heat exchange pattern provides heat energy from the outer surface of drier to paper.The example of drum dryer includes, but are not limited to Yankee or its improvement that traditional steam is filled; The drum dryer that other traditional steam commonly used is filled in the field of papermaking; The gas igniting drum dryer of inner heating, as produce by the Flakt-Ross of Montreal, CAN and by A.Haberl etc., " The First Linerboard Application of the GasHeated Paper Dryer ", the 77th Annual Technical Conference progress of CPPA, the B volume, Montreal, Canada, in January, 1991 is disclosed; Electrical heating roller, this cylinder are to heat by inductance in the described shell or resistive element; By inside deep fat or the oily cylinder that heats of hot fluid that links to each other with a heat exchanger; By radiation heating cylinder from the infrared radiation heating of the burner of gas and electricity component; By with the cylinder of the Contact Heating of gas of flame or heating etc.

In other embodiments, described second shifts fabric preferably has lower roughness or decorative pattern than the first transfer fabric, so that improve contacting of described paper and dryer surface, and therefore improve heat transmission, and don't destroy the described first graining effect of shifting fabric.Described second shift fabric and optionally forming fabric natural also may give described paper flower line.

In addition, the applicant has found that, even do not carry out the Yankee drying, hygrometric state paper is transferred to coarse first fast shift on the fabric, do not have and transfer to lower second the shifting on the fabric under specific MD degree of drawing and not transfer on the lower fabric of roughness post when shifting for the first time and then transfer to coarse second fast and compare when shifting similar on the fabric and have higher-strength (perhaps under specific intensity, having higher amount of tension) of roughness post not quickening (promptly do not have obvious speed poor) basically then.Someone thinks, after the operation of transferring to fast for the first time on the coarse fabric, transfer to once more and help some tensioning position of before drying finishes, loosening described paper on the lower fabric of roughness, therefore be reduced in the chance that fracture takes place or ftracture on the paper of described drying.Therefore, it is believed that, and then transfer to second second transfer step that shifts on the fabric after transferring to the operation on the coarse fabric fast, make described paper be in the kilter of drying on the Yankee cylinder subsequently, if described paper has good intensity and good stretching.

Also think, shift fabric with second kind and described paper is connected to the combination that can improve paper on the Yankee.Specifically, paper is directly shifted the method that fabric is connected on the Yankee from first can go wrong when the height operation usually, separate because described paper can not shift fabric from first of described three-dimensional or height graining well.This phenomenon occurs and be because occur shifting fast or after dewatering with different pressure described paper tend to be embedded in the described fabric.When shifting fabric with described letterweight on described Yankee the time by first, described paper may still be connected first and shift on the fabric, and causes the fracture of adhesion or paper.But, transfer on the second transfer fabric by described paper is shifted fabric from first, described paper does not separate with the described first transfer fabric with might being destroyed.Described paper can not be connected second usually well and shift on the fabric, second shifts fabric preferably (for example has less decorative pattern than the first transfer fabric, have the less crest that forms by its lip-deep solid factor and the height of trough), therefore can by second shift fabric with described letterweight on the drum dryer surface, and separate, and can not produce adhesion or cause the defective of the paper of other old model with described paper.

Wet paper is connected on Yankee or other heat drier surface preferably with the less pressure to paper finishes, so that most of decorative pattern that reservation is given by the fabric of front.The conventional method that is used to have produced wadding is not suitable for this purpose, because in described method, described letterweight is formed intensive flat form on Yankee with a pressure roll, transmits so that carry out to greatest extent heat by conduction.The present invention should use lower pressure.Specifically, the pressure that is applied on the described paper should be lower than about 400psi, preferably is lower than about 150psi, more preferably less than about 60psi, as the about 50psi of about 2-, more preferably less than about 30psi.Be applied to pressure on the described paper and be and comprising that what measure on 1 area in square inches in maximum pressure district is the average pressure of unit with psi (pound/square inch).What measure at maximum pressure point be that the pressure of unit is preferably about 100pli (pound/linear inch) or lower with every linear inch pound (pli), 50pli or lower preferably approximately, more preferably about about 30pli of 2-.

Described pressure roll can also separate with described drum dryer, and contact described paper and the drum dryer surface that is modified between, replaced by the fabric tension of fabric wrapping part.No matter whether described pressure roll contacts, and second length that shifts fabric winding drum dryer machine direction is at least about 2 feet, and preferably about at least 4 feet, more preferably about at least 7 feet, more preferably about at least 10 feet.Concerning relating to the embodiment that obvious fabric twines, the length that fabric twines should be no more than described drum dryer the machine direction girth 60%, preferably approximately 40% or lower, more preferably about 30% or lower, about 5-about 20% most preferably.Described fabric preferably twines the length that is less than the complete length that this fabric contacts with drier of described drier, and particularly, described fabric separated with described paper before this fabric enters the drier cover.The length of fabric wrapping depends on the roughness of this fabric.

Suppose to have avoided the compression-type dehydration already before paper being layered on the drum dryer surface, the low pressure lay helps to keep substantially density uniformly on the paper of drying.By improving uniform substantially density with the non-compression method aridity that reaches higher of dewatering effectively before connecting carrying out Yankee.Specifically, preferably dewatering to reach by non-compression when being placed into described paper on the drum dryer is higher than about 25% denseness, preferably is higher than about 30%, as about 32%-about 45%, more preferably be higher than about 35%, about 50% as about 35%-, more preferably greater than about 40%.In addition, selected that the preferred less big elasticity of the fabric of described letterweight on drum dryer is outstanding, these are given prominence to can apply big local pressure to described paper.Except normally used conventional paper tinsel and vacuum tank, can be used for replenishing the technology of dewatering and comprise an air press, wherein, pressure-air is by wet paper, so that the eliminating liquid water, capillary dehydration and steam treatment etc.

In specific embodiments, can unruffled described paper be separated from the dryer surface of Yankee and other heating.A kind of Interface Control mixture that contains viscous compound and release agent that separates described paper that is applicable to is disclosed in the U.S. Patent application serial number of being applied on the same day by F.G.Drueck etc. and the application (the unknown) wrinkle resistantly, be entitled as " method of producing low density resilient webs ", this patent is made this paper list of references by receipts.In addition, can carry out described paper wrinkling, particularly slightly wrinkling from the described drum dryer surface.Slight wrinkling its surface configuration that can keep is constant relatively, and is adsorbed on the drum dryer with very low absorption affinity.Wrinkling bonding agent and/or Chemical Decomposition agent can be coated on the surface of the surface of described paper or described drum dryer, so that improve effectively separating of bonding and/or described paper and dryer surface.

The step that was used for before shifting fast elementary paper is carried out partial dehydration can be finished with any method well known in the art.Be dewatered to fiber consistency and be lower than approximately 30%, preferably do not heat basically.The dewatering that does not heat comprises by gravity, water dynamic force, centrifugal force, vacuum or applies gas pressure etc. allows water flow out from the fabric of moulding.The partial dehydration that is undertaken by heating means not can comprise by on the fourdrinier machine double-long net shape make-up machine or on use paper tinsel and vacuum tank to realize dehydration on the improved fourdrinier machine of fourdrinier wire, comprise by W.Kufferath etc. at Das Papier, vibrating roller disclosed in 42 (10A): the V140 (1988) or " shake " roller " sound wave roller ", pressure roller, suction roll or other device known in the art.Different gas pressures or the hair suction pressure that is applied on the described paper also can be used for discharging liquid water from described paper, as disclosed in the following document air pressure provided: is the U.S. Patent application serial number 08/647 on May 14th, 1996 by M.A.Hermans etc. in the applying date, disclosed in 508, be entitled as " method and apparatus that is used to produce soft paper " and, be entitled as " the air press that is used for the l Water Paper dehydration " by the U.S. Patent application serial number (the unknown) that F.Hada equals to apply on the same day; Be disclosed in the US5 that authorized I.A.Andersson etc. on July 27th, 1993, the paper machine in 230,776, be disclosed in and authorized US5 on February 4th, 1997,598,643 and authorize the US4 of S.C.Chuang etc. on December 3rd, 1985, capillary dehydration technique in 556,450; With by J.D.Lindsay in " discharge dehydration so that keep bulk ", Paperi ja Pun, 74 (3): 232-242 (1992); More than all documents all made this paper list of references by receipts.Described air press is particularly preferred, because it can just apply economically by machine being compared simple transformation, and produces high efficiency and good dehydration.

Described quick transfer step can be carried out with several different methods known in the art, particularly be disclosed in the U.S. Patent application serial number 08/790 that the method in the following document: Lindsay equals application on January 29th, 1997,980, be entitled as " improving the method that shifts fast, " so that big the folding that produces high bulk and do not have; Equal the U.S. Patent application serial number 08/709,427 of on September 6th, 1996 application by Lindsay, be entitled as " method of producing high bulk paper with non-woven substrate "; Authorize the US5 of S.A.Engel etc. on July 16th, 1997,667,636; With authorize T.E.Farrington on March 4th, 1997, the US5 of Jr. etc., 607,551, above document is made this paper list of references by receipts.In order to have good paper performance, the described first fabric roughness (as hereinafter defined) that shifts fabric is approximately the 30%-about 300% of the diameter of the largest warp of this fabric or weft yarn, more preferably about 70%-about 110%, perhaps concerning bondedfibre fabric, on the surface of fabric, have the highest slim-lined construction because of width is arranged.Usually, the yarn diameter of yarn is about 0.05 inch of about 0.005-, about 0.035 inch of particularly about 0.005-, about 0.020 inch of more preferably about 0.010-.

Shift for the acceptable heat on the dryer surface, described paper can shift fabric from first and transfer on the second transfer fabric, preferably has the roughness that is lower than the first transfer fabric.Described second roughness that shifts fabric is preferably about 0.9 or lower with first ratio that shifts the roughness of fabric, and particularly about 0.8 or lower, more preferably approximately 0.3-is about 0.7, more preferably about 0.2-about 0.6.Similarly, described second surface thickness that shifts fabric preferably is lower than the surface thickness of the first transfer fabric, second surface thickness and first ratio that shifts the surface thickness on the fabric that shifts on the fabric that make is approximately 0.95 or lower, more preferably about 0.85 or lower, more preferably approximately 0.3-is about 0.75, more preferably about 0.15-about 0.65.

Although textiles because its low-cost and maneuverability is the most frequently used, has had non-woven material and in the substitute that is developed to as traditional forming fabric and pressure felt, and can be used among the present invention.Its example comprises the U.S. Patent application serial number 08/709,427 that is equaled application on September 6th, 1996 by J.Lindsay, is entitled as " method of producing high bulk paper with non-woven substrate ".

On the other hand, the present invention relates to the paper produced with said method.In specific embodiments, described paper has: about at least 0.1 millimeter surface thickness (as hereinafter giving a definition), preferably about at least 0.2 millimeter, more preferably about at least 0.3 millimeter; ABL value (as hereinafter giving a definition) is at least 0.2km; The amount of tension of machine direction is at least 6%; And/or be at least 6% perpendicular to the amount of tension of machine direction.

Be not subjected to the wrinkling restriction that produces, the chemical characteristic of described no wadding can change, so that obtain new effect.For example, when wrinkling, a large amount of release agents or paper softener may disturb bonding with Yankee, but in no wrinkle pattern, can use higher addition.Can add emollient, washing lotion, wetting agent, skin conditioner and such as the silicone compounds of polysiloxanes etc. with desirable high-load now, and rare by the wrinkling restriction that produces.But, in fact must be in addition careful, so that paper is shifted on the fabric and can suitably separate from second, and keep bonding to the minimum level of dryer surface, so that efficient drying and control are slided.The principle that reaches described purpose is disclosed in the U.S. Patent application serial number of being applied on the same day by F.G.Druecke etc. and the application (the unknown), is entitled as " method of producing low density resilient webs ".But, do not relying under the wrinkling prerequisite, the present invention compares with process for creping has the bigger free degree aspect the novel moistening final compound of use and other chemical treatment.

The fiber of a lot of types can be used in the above-mentioned embodiment, comprises hardwood or cork, straw, flax, cow tree seed floss silk fibre, abaca, hemp, mestha, bagasse, cotton and reed etc.Described known paper fibre can use, comprise bleaching and unbleached fiber, natural fabric (comprises xylon and other cellulose fibre, cellulose derivative, with chemicosolidifying or crosslinked fiber) or synthetic fiber (synthetic paper fibre comprises by polypropylene, acrylic acid, the virtue acid amides, the fiber of certain form made from acetic acid esters), natural fabric and recovery or the fiber that utilizes again, hardwood and cork, with fiber by machinery making beating (for example, ground wood pulp), chemical pulping (including, but are not limited to brown paper and sulphite pulping process), mechanical pulping of heat and chemi thermo mechanical pulping etc.Can use the mixture of above-mentioned any kind fiber or relevant fiber type.

In one embodiment, it is about 10% or higher high yield fiber that described fiber slurry contains percentage, preferably approximately 20% or higher, more preferably about 50% or higher, more preferably be higher than 70%.The paper made from the high yield fiber tends to have wet elasticity highly.When the wet strength agent with effective dose adds in described slurry or the paper, can also improve wet elasticity, wet: dried draw ratio is approximately 10% or higher, and preferably approximately 20% or higher, more preferably about 30% or higher, more preferably about 40% or higher.Can also about 10% or higher concentration, preferably approximately 25% or higher concentration use strengthen or the crosslinked fiber of chemistry so that improve wet elasticity in certain embodiments.For cost and other reason, certain embodiments of the present invention may comprise and contain about 10% or the paper of higher recycled fiber, preferably approximately 20% or higher recycled fiber, more preferably about 30% or higher recycled fiber, even 100% be recycled fiber basically.

Can be used for fiber of the present invention can prepare with several different methods known in the art.The method that can be used for preparing fiber comprises disperses to curl and improve drying property so that produce, as authorize the US5 of M.A.Hermans etc. on September 20th, 1994,348,620 and authorize the US5 of M.A.Hermans etc. on March 26th, 1996,501, disclosed in 768, above patent is made this paper list of references by receipts.Can adopt fiber type, fiber-treating method and such as the various combinations of the paper forming method of quick transfer, so that produce paper of the present invention.

Can also use chemical addition agent, and can add fibrillation, fiber slurry to or add on the paper at production period or after producing.Described additive comprises opacifier, pigment, wet strength agent, dry strength agent, softener, emollient, wetting agent, virucide, bactericide, buffer, wax, fluoropolymer, odour controlling materials, zeolite, dyestuff, fluorescent dye or brightening agent, aromatic, desizing agent, vegetable oil and mineral oil, wetting agent, sizing agent, super absorbent, surfactant, wetting agent, ultraviolet inhibitor, biocide, washing lotion, fungicide, preservative agent, the Lu Yun extract, or vitamin E etc.The use of chemical addition agent is not necessarily uniform, but can change the position, and from the one side of described paper to another side.The lip-deep hydrophobic material of a part that is deposited on described paper can be used for strengthening the performance of described paper.

Can use single hopper or a plurality of hopper.Described hopper can be a stratification, so that can produce the paper of sandwich construction with single hopper shower nozzle.Described paper is preferably produced with the hopper of stratification or stratiform, so that preferably will be than the one side of short fiber laydown at described paper, obtaining improved pliability, and will be than long fiber laydown at the another side of described paper or be deposited on the internal layer with the paper more than three layers or three layers.Described paper is preferably produced on the porose forming fabric of annular, and this fabric can make liquid flow out and paper is carried out partial dehydration.Can the mechanical or chemical connection of dampness paved in multi-layers from a plurality of elementary paper of a plurality of hoppers, to form a kind of single paper with multilayer.

Can understand various feature and advantage of the present invention by following explanation.In this manual, in conjunction with the accompanying drawing that is used to illustrate the preferred embodiment of the invention.Described embodiment is not represented all scopes of the present invention.Therefore, also will be with reference to claims of the present invention, so that explain complete scope of the present invention.

Brief description of drawings

Fig. 1 schematically shows the sectional view in a kind of quick transfer gap, wherein paper is transferred on the dapple transfer fabric from a kind of support fabric.

Fig. 2 is shown schematically in the sectional view after transferring on the three-dimensional transfer fabric fast.

Fig. 3 schematically shows the schematic process flow diagram of a kind of embodiment in explanation paper machine of the present invention cross section.

Fig. 4 schematically shows the schematic process flow diagram of second kind of embodiment in explanation paper machine of the present invention cross section.

Fig. 5 schematically shows the schematic process flow diagram of the third embodiment in explanation paper machine of the present invention cross section.

Fig. 6 schematically shows the schematic process flow diagram of the 4th kind of embodiment in explanation paper machine of the present invention cross section.

Fig. 7 schematically shows the schematic process flow diagram of the data and curves that the physical characteristic that shows some paper is described.

Term definition and method

In this article, " thickness " of paper refers under the load of 0.05psi the thickness measured with the platen base thickness measurement equipment of 3 inch diameters, except as otherwise noted.

In this article, " the MD tensile strength " of pattern product is to well known to a person skilled in the art when the stretching paper carried out along machine direction the conventional index of the load of per unit width on breakaway poing. Similarly, " CD tensile strength " is that the edge is perpendicular to the similar index of the direction detection of machine direction. MD and CD tensile strength are measured with an Instron instron tensile strength tester, use the crosshead speed of 10 inches of 3 inches jaw width, 4 inches jaw span and per minutes. Before measuring, relevant sample remained under the TAPPI condition (73 °F, 50% relative humidity) 4 hours. Tensile strength is (on breakaway poing, the reading of described Instron gram is divided by 3, because the test width is 3 inches) take the grams of per inch as unit representation.

" MD stretching " and " CD stretching " refers to that described sample is at the percentage that stretched during the tensile test before fracture. Paper produced according to the invention can have about 3% or higher MD stretch, such as about 4%-24%, about 5% or higher, about 8% or higher, about 10% or higher, more preferably about 12% or higher. It mainly is by the hygrometric state paper matrix is produced on highly crooked fabric that the CD of paper of the present invention stretches. CD stretches can be about 4% or higher, about 6% or higher, about 8% or higher, about 9% or higher, about 11% or higher, or about 6%-15%.

In this article, " ABL " factor (adjusting breaking length) of paper is that MD tensile strength is divided by basic weight, take km (km) as unit representation. For example, a kind of MD tensile strength be 300 grams/inch and basic weight be 30gsm (g/m) the ABL factor that has of paper be (300 grams/inch)/(30 g/ms) * (39.7 inches/meter) * (1 km/1000 meter)=0.4 km.

In this article, " wet: as to do ratio " is that the wet tensile strength of geometric average is divided by the ratio of geometric average dry tensile strength. Geometric average tensile strength (GMT) be described paper machine direction tensile strength and perpendicular to the long-pending square root of machine direction tensile strength. Except as otherwise noted, term " wet: dry tensile strength " expression " geometric average tensile strength ". It is wet that paper of the present invention has: dried ratio is approximately 0.1 or higher, more preferably be approximately 0.15 or higher, more preferably be approximately 0.2 or higher, more preferably be approximately 0.3 or higher, more preferably be approximately 0.4 or higher, more preferably about 0.2-about 0.6.

In this article, " the high speed operation " or " industrial useful speed " that is used for paper machine refers to that machine speed equates with any of lower train value or scope at least, take the footage of per minute as unit: 1,000; 1,500; 2,000; 2,500; 3,000; 3,500; 4,000; 4,500; 5,000; 5,500; 6,000; 6,500; 7,000; 8,000; 9,000; 10,000; With the scope with upper and lower bound of any in the above-mentioned numerical value.

In this article, " industrial valuable dryness level " can be about 60% or higher, about 70% or higher, about 80% or higher, about 90% or higher, and approximately 60%-95%, or about 75%-95%. For the present invention, described paper should be dried to industrial valuable dryness level at drum dryer.

In this article, " surface thickness " refers to dapple three-dimensional surperficial distinctive crest-trough difference in height. It can represent distinctive thickness or the height of mold-made paper structure. The specially suitable method of measuring surface thickness is Mor stripe interferometer, and this instrument can carry out Accurate Measurement and not have surperficial distortion. For reference material of the present invention, the white light visual field that should computerized control skew Mor stripe interferometer is measured surface configuration, adopts about 30 millimeters visual field. Use the principle of this system to be disclosed in Bieman etc., " absolute determination of carrying out with the field offset Moire fringe ", SPIE optics meeting progress, 1614 volumes, 259-264 page or leaf, 1991. A kind of suitable commercial apparatus of Mor stripe interferometer is to be made 38 millimeters the visual field (visual field in 37-39.5 millimeter scope is suitable) by the CADEYES  interferometer (Farmington Hills, Ichigan) that Medar company produces. CADEYES  system uses white light, and this light projects thin black lines on the described sample surface by a grid projection. By a described surface of similar gridding observing, produce fringe, observe described edge with a CCD camera. Adjust optical image with suitable camera lens and stepper motor, carry out the movement (technology as mentioned below) of visual field. A video processor sends to a PC computer with the fringe image of catching, and processes, so that according to the details by the relevant apparent height of the anti-release of the viewed edge pattern of gamma camera. Former reason J.D.Lindsay and the L.Bieman of the crest of the distinctive paper of use CADEYES network analysis-trough height disclose, " utilize the tangible characteristic of Mor stripe interferometer research paper ", Proceedings of the Non-contact, Three-dimensional Gaging Methods and Technologies Workshop, manufacturing engineer association, Dearborn, Michigan, 4-5 day in March, 1997.

Those skilled in the art can (be in the situation about being produced by textile design in structure for the identification of distinctive unit interval structure with the height image of described CADEYES form data subsequently, usually with its arrangement arranged side by side as floor tile, in order to cover larger two-dimensional areas), and measure typical crest and the trough degree of depth on described structure or other any surface. A kind of simple method that achieves the above object is to extract two-dimentional altitude curve from the lines that are drawn on the described Terrain Elevation figure, a regularly representative part of the sufficient amount on surface is perhaps passed through at the highest and minimum position of this described unit interval of curve negotiating. Described altitude curve can be analyzed the distance of crest and trough subsequently, if described curve is to obtain from the paper that is in more flat state when measuring or the part of paper. The impact of disturbing in order to eliminate accidental optical interference and possible outside should be got rid of the highest 10% and minimum 10% of described curve, and with the altitude range of all the other points as its surface thickness. Say that technically the method requires to calculate us and is referred to as the variable of " P10 ", this term is defined as the difference in height between the 10% and 90% material benchmark. The concept of related materials benchmark is well-known in the art, such as L.Mummery in the surface detail analysis: handbook, Hommelwerke GmbH, Muhlhausen, Germany is disclosed in 1990. In the method, described surface is regarded as a kind of transition from the air to the material. For specific curve, with regard to the paper that keeps flat, the height of high crest of the maximum height of described surface beginning--be the height of " 0% reference line " or " 0% line of material ", the length that is illustrated on the described height 0% horizontal line is occupied by material. Along the horizontal line by described curve minimum point, 100% line is occupied by material, so that described line becomes " 100% line of material ". At (between the maximum point or point at described curve) between the line of material of 0%-100%, the part of the horizontal line length that is occupied by material will increase simply along with the reduction of this line height. Described material proportion curve provides along the horizontal relation of the height of the horizontal material part by described curve and described line. The accumulation that described material proportion curve also is a kind of curve highly distribute (term should be " material part curve " more accurately).

In case set up described material proportion curve, can use it for the crest height that limits a kind of distinctive curve. P10 " distinctive crest and trough height " parameter is defined as the difference between the height of line of material of 10% line of material and 90%. Described parameter is stronger in the outside or abnormal marginal portion of described typical curve structure, and P10 is highly had less impact. The unit of P10 is millimeter. A kind of surface thickness of material is with P10 surface thickness value representation, and expression comprises the curve of limit height in the typical flat interval on described surface. " meticulous surface thickness " is the P10 value along the curve at this surperficial position, plane, and it is being uniform aspect the height aspect the curve of the minimum and maximum part that relatively comprises described unit interval. If there are two sides, what measure is the side with maximum decorative patterns of this material.

Surface thickness is for checking the shape that produces at substrate, particularly before the drying process and the feature that produces at described paper during the drying process, but, same be used for getting rid of the large-scale shape that transforms operation institute " manually " generation in drying, described operation such as embossing, perforate, wrinkling etc. Therefore, the curve that checks should be taken from the position that does not have embossing, if described paper is embossed, perhaps measures the paper of not embossing. Surface thickness is measured and should be got rid of large scale structure, such as wrinkle and the folding of the three-dimensional character that can not embody original substrate itself. Already recognized, can weaken the shape of paper by calendering or other operation that can affect whole base paper. Surface thickness is measured and can suitably be carried out on calendering paper.

In this article, " lateral length size " refers to a kind of peculiar size of dapple three-dimensional paper, and described paper has a kind of decorative pattern that comprises the unit interval of repetition. Polygonal minimum widith around the protrusion of described unit interval is regarded as described lateral length size. For example, be to have about 1 millimeter of the vertically interval of repetition, along on the paper of thoroughly doing on the fabric of the about 2 millimeters rectangular depression in machine direction interval, its lateral length size should be about 1 millimeter. Described dapple fabric (shifting fabric and felt) can have periodic structure in this article, this structure has lateral length size at least a in the following numerical value: about 0.5 millimeter, about 1 millimeter, about 2 millimeters, about 3 millimeters, about 5 millimeters, and about 7 millimeters.

In this article, " MD unit interval length " refers to the length (span) of the machine direction of distinctive unit interval on fabric or paper, it is characterized in that having the structure of repetition. The dapple fabric that discloses in the present invention (shifting fabric and felt) can have periodic structure, and this structure has lateral length size at least a in the following numerical value: about 1 millimeter, about 2 millimeters, about 5 millimeters, about 6 millimeters and about 9 millimeters.

In this article, " fabric roughness " refers to cross over the distinctive maximum vertical range of the upper surface that can contact the dapple fabric that is deposited on the paper above it.

In one embodiment of the present invention, one or both of described transfer fabric are the US5 that authorize July 4 nineteen ninety-five such as K.F.Chiu etc. according to being disclosed in, and the technology in 429,686 is produced, and the document is included as this paper list of references. Be disclosed in the load layer that three dimensional fabric of the present invention has the machine surface of close this fabric, and have three-dimensional rag layer on the paper pulp surface of this fabric. Connection between described bearing bed and the rag layer is called as the sub-level face. Described sub-level face is to be formed by the top that the minimum CD on the described bearing bed saves. The rag that is positioned at the paper pulp surface of described fabric is used for producing the anti-visual marking at the paper pulp paper that is carried by this fabric.

Peak by described rag layer forms a upper surface, and " marking " warp thread partly forms on the MD marking joint by being located on the top of described rag layer, and the upper plane of this rag layer is formed at its top. The remainder of this rag layer is higher than described sub-level face. A mid-plane is formed at the top of the highest described CD joint, and this plane may coincide with described sub-level face, but more commonly a little more than described sub-level face. This mid-plane must be lower than the certain distance in described upper plane, and this distance is called as " plane is poor ". Can be regarded as " roughness of fabric " by the fabric of the disclosures such as Chiu or " plane is poor " of similar fabric. For other fabric, the roughness of fabric is regarded as the vertical drop between the minimum surface that might contact paper of the highest part of described fabric and this fabric usually.

A kind of specific index relevant with the fabric roughness is " putty roughness factor ", wherein, measures the vertical span of the putty marking of described fabric. The Dow Corning  Dilatant compound 3179 that to sell take SILLY PUTTY as trade mark is heated to 73 °F, and to be fused into a diameter be 2.5 inches, and thickness is 1/4 inch dish. Described dish is placed on an end of a brass cylinder, and making its quality is 2046 grams, and measures 2.5 inches diameter and 3 inches height. Fabric to be determined is placed on the clean surface of solids, and will will have the cylinder of putty to put upside down at the one end, and put lightly described fabric. Weight by described cylinder is pressed in described putty on the described fabric. Allow described weight remain on described putty dish upper 20 second, at this moment, described cylinder lifted lightly and usually successfully with described putty band on it. Now can be surperficial by the dapple putty that optical method measuring contacts with described fabric, in order to obtain the estimated value of typical maximum crest and trough difference in height, this estimated value is weighed with P10 parameter mentioned above. The measured value of reporting is the maximum of two average P10 values, and one of them value is machine direction, and another is vertical direction. Mean value on direction is the average P10 value that is parallel at least 10 curves parts of interested direction, each curve partly is approximately 10 millimeters long or longer, and separate on described surface, in order to obtain the rational representative of topnotch difference on this surface. For example, when mean value is when obtaining from vertical direction, the putty marking of some Lindsay Wire TAD fabrics with machine direction structure of prolongation may produce maximum average P10 value. For example, a kind of fabric average P10 value of (CD) on perpendicular to machine direction is 0.68 millimeter, is 0.47 millimeter in machine direction (MD), and the putty rugosity factor should be reported to 0.68 millimeter. The average P10 value of the CD of another kind of fabric is 0.16 millimeter, obtains according to 15 curves of 20 millimeters long, and correspondence is to be 0.64 millimeter in machine direction therewith, and its putty rugosity factor should be reported to 1.16 millimeters. A kind of useful device that is used for described mensuration is above-mentioned CADEYES Mor stripe interferometer, has 38 millimeters the visual field. Described mensuration should be carried out within 2 minutes after removing the brass cylinder.

The porosity of described fabric determines that it allows air or moisture or the water ability by this fabric, in order to obtain the moisture of the desirable paper that is carried by this fabric. Described porosity is by the orientation of warp thread and weft yarn in warp count (warp thread cover percentage) and this fabric and interval determination.

In this article, term " dapple " or " three-dimensional " that be used in the surperficial front of fabric, felt or non-calendering paper represents that this surface is not smooth with coplanar basically. Specifically, it represents that a kind of surface thickness, fabric roughness or the putty roughness value on described surface are at least 0.1 millimeter, such as about 0.2-about 0.8 millimeter, preferably at least 0.3 millimeter, such as about 0.3-1.5 millimeter, more preferably at least 0.5 millimeter, more preferably at least 0.7 millimeter. In specific embodiments of the present invention, a described * is 0.2 millimeter-2.0 millimeters, more preferably the described first putty roughness that shifts fabric is at least 0.5 millimeter, and the second putty roughness that shifts fabric hangs down about 20% than the first putty roughness that shifts fabric at least.

Total warp thread quantity that " warp count " is defined as on the per inch fabric width multiply by the diameter through sliver that represents with inch, multiply by 100.

We said " warp thread " and " weft yarn " refers to the fabric that weaves at a loom, warp thread is along the yarn of this fabric by direction (machine direction) distribution of papermaking device operation, and weft yarn is perpendicular to machine direction (vertical direction) distribution. It will be understood by those skilled in the art that described fabric to be made makes warp thread along distributing perpendicular to the direction of machine and weft yarn being distributed along machine direction. Described fabric can be used among the present invention, described weft yarn is considered as the MD warp thread, and described warp thread is considered as the CD weft yarn. Described warp thread and weft yarn can be circular, flat or banded, or are the combination of above shape.

In this article, " high yield paper pulp fiber " provides output is about 65% or higher, more preferably about 75% or higher, and the more preferably about paper-making fibre produced of the pulping process of 75%-about 95%. Output is the acquisition amount with the processing fiber of the percentage expression of original timber quality. Described pulping process comprises the chemi thermo mechanical pulping (BCTMP) of bleaching, chemi thermo mechanical pulping (CTMP), pressure/pressure heat engine tool pulping (PTMP), heat engine tool pulping (TMP), heat engine tool chemistry pulping (TMCP), the high yield sulfite cellulose, the high yield kraft pulp, more than the fiber that obtains of all methods have the lignin of high-load. The high yield fiber studies the hardness of pulp fibres and famous (hardness under dry and moistening state) with its relative typification. The cell of brown paper and other non-high yield fiber tends to more soft because on its cell membrane and lignin, " colloid " or " glue " in some cell membrane removed by major part. Lignin is still non-bloating in water, and is hydrophobic, and can resist water to the emollescence of fiber, for the brown paper fiber, remains on the pliability of cell membrane in the moistening high yield fiber. The feature of described preferred high yield paper pulp fiber also be to comprise than more completely, relatively unimpaired fiber, the high free degree (the 250 Canadian standard frees degree (CSF) or higher, more preferably 350CSF or higher, more preferably 400CSF or higher), and low granule content (is lower than 25%, more preferably less than 20%, more preferably less than 15%, more preferably less than 10%, determine by Britt tank mensuration). The unlikely acquisition of the paper wet elasticity performance of the present invention made from the fiber that reclaims is because caused infringement to fiber during mechanical treatment. Except above-mentioned paper-making fibre commonly used, high yield paper pulp fiber also comprises other natural fiber, such as cow tree seed silk flosssilk wadding fiber, abaca, hemp, mestha, bagasse and cotton etc.

In this article, " wet elasticity paper pulp fiber " is to be selected from following one group paper-making fibre: fiber and the cross filament of high yield paper pulp fiber, chemicosolidifying. The fiber of chemicosolidifying and the example of cross filament comprise fiber, the HBA fiber of the alkali lye processing of being produced by Weyerhaeuser company, and be disclosed in fiber in the following patent: nineteen sixty-five is authorized the US3 of L.J.Bernardin, 224,926, " produce the method for cross-linked cellulose fibres and the product of the method ", and authorized the US3 of L.J.Bernardin, 455 in 1969,778, " by the wadding that rises of hard cross filament and the production of refining paper-making fibre ". Although can use any mixture of wet elasticity paper pulp fiber, but selected high yield paper pulp fiber is the wet elasticity fiber in a lot of embodiments of the present invention, because it has lower cost and have good fluid control performance according to hereinafter described principle use the time.

The consumption of high yield or wet elasticity paper pulp fiber can be at least about 10% dry weight or higher in the described paper, more preferably about 15% dry weight or higher, for example approximately 20%-100%, more preferably about 30% dry weight or higher, more preferably about 50% dry weight or higher. For lamination paper, can adopt identical consumption at the paper of one deck or which floor individual layer. Because wet elasticity paper pulp fiber usually its pliability is not so good as other paper-making fibre, in some purposes, be preferred in the intermediate product of end article, as put it into the intermediate layer of three-ply paper, or concerning two laminates, place it on each inside one deck of this two layers of paper.

In this article, " non-compression dehydration " and " non-compression drying " refer to respectively not relate to the part that can cause described fabric being used for from cellulose paper except the dehydration or the drying means that anhydrate of the pressure roll of obvious densification or compression or other step occur in drying or dehydration. Described method comprises to be done; Jet impingement is dry; Radial spray connects to be connected with radial slot again and connects drying, such as R.H.Page and J.Seyed-Yagoobi, and Tappi J., 73 (9): 229 (September nineteen ninety) are disclosed; Non-contact drying, dry such as air flotation, as by E.V.Bowden, E.V., Appita be (1) J.44: 41 (1991) is disclosed; The circulation of superheated steam or impact; Microwave drying and other radio frequency or dielectric drying method; Got by the water extraction that supercritical fluid carries out; Got by water extraction anhydrous, that low surface tension fluids is carried out; Infrared drying; Metallic film by contact melting is dry; With other method. Believe that three-dimensional paper of the present invention can carry out drying or dehydration with above-mentioned any non-compression drying method, and can not cause the obvious densification of paper or its three-dimensional structure with and the obvious forfeiture of wet elastic characteristic. The dry wrinkling technology of standard is regarded as the compression drying method, because described paper must be pressed on the part of desiccated surface by mechanical means, causes being pressed in the obvious densification in position on the Yankee cylinder of heating.

The detailed description of accompanying drawing

The present invention will be described in more detail below in conjunction with accompanying drawing.For for simplicity, schematically show the various jockey pulleys that are used to form some fabric operation bands, but do not number, and the similar element in different accompanying drawings has identical Ref. No..Transfer and dry papermaking apparatus and the operation that can use various routines at feedstock production, hopper, forming fabric, paper.But, show concrete conventional element, so that the occasion that can use various embodiments of the present invention is provided.

The present invention has overcome the some problems that occurred when not having wadding with quick transfer and drum drying method production.Do not wish to be bound by any particular theory, the suggestiveness mechanism of above-mentioned some problem can be discussed in conjunction with Fig. 1 and 2.Figure 1 illustrates the branchpoint of paper transfer device or pick up.L Water Paper 1 is carried by support fabric 2, moves along the direction of machine direction unanimity with first speed, and this direction is represented with arrow 6 in Fig. 1.Paper 1 is transferred on the dapple transfer fabric 3, and this fabric comprises a pattern that replaces along machine direction substantially, and this pattern comprises towards the joint 3a of paper 1 projection with away from the 3b of described paper depression.This support fabric 2 and transfer fabric 3 are suitable at described branchpoint place close.Described transfer fabric 3 is with the second speed operation of first speed that is starkly lower than described support fabric 2.Apply typical air pressure difference, paper 1 is transferred on the transfer fabric from support fabric so that assist.For example, a vacuum tank (not shown) can be placed on and shift fabric 3 times, so that force paper 1 towards this transfer fabric.

Paper 1 makes paper 1 have alternately the pattern that is made of terrace part 4 and mold pressing part 5 to the quick transfer of dapple transfer fabric 3 generally, shown in when observing perpendicular to the direction of machine.Because the joint 3a of described transfer fabric 3 or the highest outstanding position 3a contact still connect or are positioned at paper 1 on the support fabric 2, the rub surface of described paper of the slower athletic meeting of joint, and with described support fabric and shift fabric of short duration contact time inherent described fibrous paper the plane on damage.Along with the deceleration of paper 1, its possibility bending also is molded as the shape that shifts fabric 3 and/or experiences little compression (not shown), and its length is less than the length that shifts fabric.The fricting movement of the outstanding joint 3a of described transfer fabric 3 or stir and to cause the more uneven distribution that quality is connected with fiber one fiber in described paper.The platform position 4 of described paper may have maximum tension force near the peak of prominence 3a that shifts fabric 3 during differential quick transfer.

The concrete outcome that experimental research obtained by us has been shown among Fig. 2, and wherein, paper 1 is represented as described paper and had successfully transferred to three-dimensional the transfer on the fabric afterwards with 3 motions of three-dimensional transfer fabric already.Described fabric 3 moves from left to right, and is as shown in arrow 60.The position near the end of the outstanding position 3a that shifts fabric 3 of paper 1 may have projection 4a or outstanding, obviously be by due to the accumulation of the fibrous material of motion or by by with shift the contacting due to the plane strain that on described paper, is caused of fabric 3.The reference frame of the support fabric 2 that the relative edge direction consistent with machine direction moved shifts fabric 3 and moves in the other direction along the direction opposite with machine direction.Ledge 4a on the described paper 1 may form by stirring of structure of described counter motion (for paper is before shifting).Adjacent position may be the height tensioning and have a lower basic weight, described ledge 4a itself may be the height tensioning, and is particularly especially true on the one side opposite with shifting fabric of described paper.

If the paper among Fig. 2 12 directly is pressed on the Yankee drier, the position that then contains ledge 4a then is to abut against most on this Yankee.After the drying, these ledges 4a may because surface tension and fibre pulp include the chemical adhesive effect of organic compounds be applied to dryer surface or this paper on bonding agent and stick to securely on the Yankee drier.Then when the scraps of paper when Yankee is pulled away from, the weak area of attachment can damage or still stay on the Yankee drier, causes paper sheet break and defective.Perhaps or in addition, paper 1 may be by over-tension and strength reduction during removing.If paper 1 usefulness creping doctor was scraped from meeting and was caused the scraps of paper to damage this moment.But, contain or globality that the vulnerability of the high tension zone of contiguous this ledge 4a may jeopardize the scraps of paper when when Yankee or other drum-type drying surface are pulled away from the scraps of paper.This protuberance branch stays on the dryer surface, and what be accompanied by is formed breakage of this paper adjacent area and defective.This problem look like on quick transfer stencil paper and the rotary-drum drier machine dry both combine cause that paper queues, defective or damage, this is for produce the place of high-tension from the drying machine sur-face peeling because of the zone of the easiest damage.When paper was dry with industrial valuable dryness level, it is very serious that the problems referred to above become when running up.

Had found that at a possible cause producing high bulk, shift fast, produce under the specified conditions with the wrinkle resistant paper of roller drying operation problem, this has been proposed some solutions.Specifically, the paper that shifts is fast shifted once at least in the following manner again, guarantee that promptly the most weak of paper 1 or high tension zone 4 and 4a (and particularly the outermost part of the paper in these districts) can not become the maximum district that is attached to Yankee or rotary-drum drier, in case and paper help paper to throw off as far as possible when placing the cylindrical drier surface from above-mentioned fabrics.Do not go into seriously the reason that previous method causes the maneuverability difference, have found that, method disclosed herein has promoted the quality of paper and the improvement of maneuverability.

Ideally, paper 1 was reversed before being attached to Yankee, and making originally has the paper that shifts the fabric contact to contact with it when Yankee goes up when it is placed in.One embodiment of the present of invention are shown among Fig. 3.It can be on the support fabric 2 of forming fabric that a shown hygrometric state paper 1 is positioned at, and deposits the water-containing pulp from the hopper (not shown) on this forming fabric.Preferably be dehydrated in the time of on the support fabric 2 of paper and can be fit to the denseness that shifts fast, the denseness of alleged denseness for allowing a continuous paper to be shaped, as 15% or higher, particularly about 20% or higher, to improve performance.

Described support fabric 2 enters first and shifts the gap, is here assisted described paper is transferred on the first transfer fabric 3 that moves with the speed that is starkly lower than described support fabric by the first vacuum transfer boots 6.The first transfer fabric 3 is a kind of three dimensional fabrics, as Lindsay Wire T-116-3 design (Lindsay Wire Division, Appleton Mills, Appleton, the Wisconsin) or other fabric, based on the US5 that authorizes Kai F.Chiu etc., 429,686 disclosed contents.Described paper shortens in advance by the speed difference between two kinds of fabrics during shifting fast.In order to obtain optimum, first shifts fabric 3 should be to be slower than support fabric 2 about 10% or more speed operation, and preferably approximately 20% or more, more preferably about 30% or more.In specific embodiments, described first shifts the speed of fabric 3 operations than the slow approximately 15%6-about 50% of the speed of service of support fabric 2.

Fast the paper 1 that shifts shifts fabric 3 by first and carries and transfer to second and shift on the gap, and this gap is at one optionally between bellows 8 and the second vacuum transfer boots 9, and described here paper is shifted fabric 7 by second and picks up.Second shifts fabric 7 carries paper 1 and enters gap between roller 10 and drum dryer 11, here, described paper is connected on the surface of drum dryer 11.The rotation of drum dryer 11 is represented with arrow in the accompanying drawings.Second shifts fabric 7 preferably has the roughness that is lower than the first transfer fabric 3, and is suitable for described paper fully is pressed on Yankee or the drum dryer, so that improve good binding and drying.If only allow the part of described paper contact closely with described dryer surface, hot transmission can be hindered, and the speed of machine must slow down.

Paper 1 is transferred to second shift on the fabric 7 described paper is reversed, and guarantee that the weakest position (this position is position 4 shown in Figure 2 and 4a) of described paper can preferably not be connected on the dryer surface.As a result, described paper can separate from dryer surface subsequently, has the less danger that paper destroys takes place.

Described paper moves on roller 10a then, and compressing is on the surface of drum dryer 11.Roller 10a can oppress dryer drum 11, so that about 100pli or lower linear load are provided, and 50pli preferably approximately, the more preferably about about 30pli of 2-.Roller 10a optionally leaves drier 11, so that do not have the compressibility roll gap on the point on the surface of described paper contact drying device cylinder.Described fabric 7 twines described dryer drum along described drier its perimeter, so that enough residence times are provided, allows described paper be connected on the described cylinder, rather than is connected on the second transfer fabric 7.Therefore, when described fabric from described cylinder during around roller 10b unwinding, described paper still is connected on the described drying drum.The part that the second transfer fabric twines described cylinder girth can be approximately 5% or higher, and more preferably about 15% or higher, more preferably about 10%-about 15%.In order to carry out good connection and to separate, may need suitable compound to be sprayed on the described drum dryer surface with spray boom (not shown) or other device, and be sprayed on the second transfer fabric, as by F.G.Druecke etc. with the application's the applying date apply on the same day be entitled as disclosed in " method of producing low density resilient webs " U.S. Patent application serial number (the unknown).

Handle problems in order to help the heat transmission and to alleviate paper, it is necessary wearing certain fabric on described drum dryer surface.If described fabric separates prematurely, described paper might stick on the fabric, rather than is bonded on the drum dryer surface, unless with very big pressure with described letterweight on dryer surface.Certainly, using big pressure to mean need non-substantially compression-type handle so that be a kind of unfavorable solution when obtaining best bulk and wet elasticity.Described fabric preferably keep be positioned at dryer surface on paper contact, reached about at least 40% denseness already up to described paper, preferably about at least 45%, more preferably about at least 50%, more preferably about at least 55%, more preferably about at least 60%, so that improve its performance.Be applied to pressure on the described paper preferred (although be not must) in the 0.1-5psi scope, more preferably in the 0.5-4psi scope, more preferably in the 0.5-3psi scope.

After described paper was connected on the described dryer surface, it might do further drying with high temperature air impingement hood 12 or other drying device.Then the dry paper of part is separated from the surface of drier 11, if necessary, the paper 14 that separates is done further dried (not shown), perhaps before reeling, do other processing.

Figure 4 illustrates another embodiment of the present invention, wherein, paper 1 is positioned on the support fabric 2, and up to the denseness that reaches about 10%-about 30%, at this moment, described paper is transferred to first at first branchpoint and shifted on the fabric 3 by vacuum transfer boots.Described first shifts fabric 3 has obvious pore volume greater than described support fabric, and preferably has a 3D shape, it is characterized in that having the joint of outstanding machine direction, these joints surpass at least 0.2 millimeter at maximum vertical direction joint, preferably at least 0.5 millimeter, more preferably about at least 1 millimeter, in specific embodiments, the joint of described machine direction surpasses about 3 millimeters of the about 0.8-of joint of maximum perpendicular direction.

Described wet paper runs to second branchpoint, and a bellows 16 and vacuum tank 15 cooperations are here transferred to second with described paper and shifted on the fabric 7, and described second shifts fabric may be faster than the speed of service of the first transfer fabric 3.Second shifts fabric 7 preferably has and is approximately first and shifts fabric 1/2 or lower fabric roughness, its prerequisite be applied to all major parts that shift fast on the described paper mainly occur in shift for the first time during.If being applied to all major parts that shift fast on the described paper mainly occurs in and transfers to second and shift during the fabric, it is more coarse to be necessary to make the second transfer fabric to shift fabric than first, and preferably its fabric roughness ratio first shifts fabric high at least 30%.Transfer can be carried out at any branchpoint or at two branchpoints fast.The absolute velocity difference that quick amount that shifts and described paper are during transfer experienced is proportional, and described speed is unit with the feet per minute clock.

After on transferring to the second transfer fabric 7, described paper is by an optionally non-compression processed, air press as shown in Figure 4.This air press comprises a high pressure upper channel 17 and a bottom vacuum tank 18 that is matching relationship, so that the pressure-air from passage 17 enters vacuum tank 18 by described paper, thus described paper is dewatered to preferably approximately 30% or higher denseness, more about 32% or higher, more about 33% or higher.Can also place another supports fabrics (not shown) that contacts with paper 1, so that described paper shifts described letterweight between fabric 7 and this supports fabrics second during by described air press motion.Suitable air press is disclosed in the following document: the U.S. Patent application serial number 5 that is equaled application on May 14th, 1996 by M.A.Hermans, 647,508, be entitled as " method and apparatus of producing soft paper ", and equal the U.S. Patent application serial number (the unknown) applied on the same day with the application by F.Hada, be entitled as " the air press that is used for the l Water Paper dehydration "; Above document is made this paper list of references by receipts.

Described paper passes through roller 10a then, and is crushed on the surface of dryer drum 11.Fabric 7 can twine described dryer drum, up to its unwinding and being wound up on the roller 10b from this cylinder.At after separating from the second transfer fabric 7, described paper rests on the surface of drum dryer 11, and passes through an optionally drier cover 12, it is characterized in that carrying out the high speed impact of hot-air.Drive by means of another roller 20 and other roller or conveyer belt then and send paper 14 coilings 21 of system with drying, described system is normally preferred for the high bulk paper material.

As the replacement scheme of Fig. 3 and 4 disclosed paper method for turning, can change paper in first position of shifting on the fabric, so that no longer resting on first, the former outstanding position of described paper shifts on the outstanding position of fabric.The result of this position change method is the main point that can not become the contact drum dryer at described first ledge that shifts tissue paper.Referring to Fig. 5, paper 1 is transferred to one to shift on the fabric 22 than first of jogging speed operation from forming fabric 2 by the collection boots 6 that are positioned on first branchpoint.Quick position that shift, that embossed paper relative first shifts fabric construction changes by at second branchpoint described paper being transferred on the second transfer fabric 13 from the first transfer fabric 22 realizes, here the second transfer fabric is return by roller 24 (perhaps can use a vacuum shoe), on the 3rd branchpoint returned the first transfer fabric, this branchpoint was equivalent to the position of vacuum tank on the vacuum shoe 27 substantially then.It is in order to ensure these positions on the described paper in case contact with the first high-order bit that shifts on the fabric face that paper 1 described reorientated, be to contact now with first lower position that shifts on the fabric face, perhaps carry out the initial gross separation of described paper from the described fabric at least, so that help subsequently when the oppressed separation of being carried out on drier 11 surfaces time of this fabric, and cause described paper relative first to shift big the rearranging of fabric, so that reduce the chance that the weakest position the most closely is connected with drum dryer.

In order to realize the most effective relocating, notice should be placed on the path between the second and the 3rd branchpoint.As shown in Figure 5, first shift path that fabric passed through shift the path that fabric and Hard copy body are passed through between the second and the 3rd branchpoint greater than second.First difference that shifts the path of fabric and described paper must be the integer multiple of the peculiar MD unit interval length of the first transfer fabric.In addition, a little deviation must be arranged, so that the high-order bit certain distance of the first transfer fabric is departed from the position that once contact with the first high-order bit that shifts fabric of described paper now before second branchpoint.Described deviation distance is preferably 1/2 of MD unit interval length, but, in practice, described is can serve as about 0.2-about 0.8 departing from of unit with peculiar MD unit interval length, preferably approximately 0.3-is about 0.7, more preferably about 0.4-about 0.6.

When described paper is positioned on the second transfer fabric, can carry out other processing to described paper with different air pressures.As shown in Figure 5, paper further is molded into second shifts on the fabric, perhaps do further dehydration by the combination of pressure-air or a steam chest 26 and a vacuum tank 25.In this case, second shifts fabric can have decorative pattern arbitrarily, because it can not contact drum dryer.In fact, in embodiment shown in Figure 5, first shifts fabric can have greater than forming fabric 1, but less than second middle the roughness that shifts fabric, wherein, the second transfer fabric may become the main mode of large-scale decorative pattern.Therefore, transfer can mainly carried out near on first branchpoint of the first vacuum transfer boots 6 fast, and do not carry out the upset of paper, by second shift carry out on the fabric twice extra transfer get on and shifts under and paper is reorientated the maneuverability that can be improved on the first transfer fabric, by the second correct location of shifting fabric loop, guarantee described correctly carrying out of reorientating.Transmit and avoid the paper separation problem in order to improve heat, it is necessary under certain tension force the first transfer fabric being contacted the fabric winding of carrying out to a certain degree with drum dryer 11., can use such as silicone oil solution or emulsion separating agent and handle the side that described fabric contacts with paper, temporarily from the gap that the first transfer fabric separates at described paper so that after described paper is placed on the dryer surface, separate subsequently with described paper.Preferably spray 52 by a spray boom or shower nozzle 51.Also show another spray boom 53, this spray boom will be sprayed and 54 will be sprayed onto on the dryer drum 11, so that provide described paper to connect on dryer surface and the suitable balance of separating.

After described paper rotates back on the first transfer fabric 22, this paper further is molded into first to be shifted on the fabric or by mold pressing or dewatering operation 28 and does further dehydration, institute's operation can comprise a steam chest, has a vacuum tank that is positioned at below the paper, an air press, displacement dehydration, or other non-compression dewatering or graining method.Allow described paper contact drying device cylinder then, preferably has certain winding, shift fabric described paper 1 when drum dryer separates with box lunch first and still be connected on the drier, and before the drum dryer separation, do further drying at described paper by adding hot-air hood or other method.This separation is preferably finished by process for creping.

In the above-described embodiment, preferably wet paper 1 being connected Yankee goes up and paper is not carried out significant densification.Non-compression dehydration, described paper low pressure is connected to the drum dryer surface, and use the correct fabric of selecting or felt that described paper is connected to combination on the drum dryer, make that described paper can be by the outstanding position highly denseization on described fabric or the felt, can cause having substantially uniformly density or have high and low density region, the average bulk based on described paper Determination of thickness paper between flat board of described paper (inverse of density) can be about 3cc/g (cubic centimetre/gram) or higher, 6cc/g or higher preferably approximately, more preferably 10cc/g or higher, more preferably 12cc/g or higher, more preferably 15cc/g or higher.Usually high bulk paper is rolled, so that the production resultant articles.After described paper was optionally rolled, the bulk of finished product can be about 4cc/g or higher, more preferably about 6cc/g, more preferably about 7.5cc/g, more preferably about 9cc/g.

Because described fabric has three-dimensional surface with the fabric of letterweight on drier, might exist a part of advantage with described paper to be fixed on joint on the dryer surface, but, described paper preferably can be at the obvious densification of the position of described joint quilt, because before drying, carried out suitable non-compression drying, and because described fabric has applied lower pressure, therefore, the paper of being produced may have substantially density uniformly, and has wet strength agent, the dried distribution uniform or heterogeneous of strengthening compound, salt, dyestuff or other additive and compound.

Figure 6 illustrates another embodiment of the present invention, this scheme is similar to the embodiment before shifting for the second time shown in Figure 3.When shifting for the second time, paper 1 can be placed on second and shift on the fabric 7, from described paper being connected on the drum dryer 11 by applying conventional roller load or nip pressure with a pressure roll 30 here.This can cause producing dapple densification by the porose fabric 7 that is pressed into described paper on paper 1.Fabric 7 can be wrapped on the drier 11, but the degree of twining is lower, and as shown in the figure, the winding degree is lower than 5% of drier girth.In a single day paper 1 be connected on the drum dryer 11, can hold or the contacting of fixing and the area of heating surface by optionally other dry fabric 32 environmental protection, keep contacting by roller 33 with the part on drum dryer surface, described roller can be exerted pressure to dryer drum, perhaps can separate a segment distance with dryer surface, so that described roller does not produce direct power on drier, but produces tension force on fabric 32.Fabric 32 should the speed motion identical with the lip-deep paper of drum dryer 1, but needs certain speed difference in certain embodiments, so that softening described paper is at air side surface or carry out other improvement.Fabric 32 can be graining or figuratum, and can have 3D shape.

As shown in Figure 3, be positioned on the drier 11 paper by from cover 12 the heat transmission that adds hot-air carry out drying, before separating with dryer surface now by the conduction of drier itself drying.Separation process is preferably finished in unruffled mode, but creping doctor can be arranged, so that assist the separation of paper.

Embodiment

The following examples are used to illustrate the possible scheme relevant with the present invention, wherein, have obtained improved fluid control, pore volume and surface detail by the disclosed new structure of this paper.Concrete consumption, ratio, composition and parameter are to be used for schematically, rather than will specifically limit scope of the present invention.

Example 1

For from the fabric to fabric transfer being described after quick transfer step for the second time in the effect of improving aspect the characteristic of some paper, one with saturating dried device work, and do not have to test on the model paper machine of dryer drum.The purpose of this test is in order to check the quick transfer method effect of the transfer operation second time after first quick transfer step relatively.Dragon spruce BCTMP fiber with 40% and percentage by weight are that the brown paper cork fibrous of 60% Coosa Pines LL19 bleaching prepares the papermaking batching.Denseness with described fiber dilution to 1%.With the consumption that accounts for dry fiber weight 0.4% with the wet strong additive of KYMENE557LX (Hercules company, Wilmington, Delaware).In the first of this embodiment, disclosed a kind of preferred transfer method, with a fluid applicator speed of described slurry with 40 feet of per minutes is transported on the smooth forming fabric.With vacuum tank elementary paper is dewatered, transfer to a kind of coarse three dimensional fabric Lindsay Wire (product of Appleton Mills, Appleton, Wisconsin) T-116-3 fabric then fast.As shown in table 1, the degree that shifts changes fast.The paper that will shift is fast transferred to the less saturating dry fabric of fabric Lindsay Wire L-452 of a kind of decorative pattern then.Dry described paper on saturating dried device, and rolling then.

In second kind of distortion, disclosed a kind of not too preferable methods, described elementary paper is not at first transferred on a kind of Albany Felt fabric Velostar800 post, then from paper being transferred to fast more coarse Lindsay Wire T-116-3 fabric here.The T-116-3 fabric has 71 * 64 order number and 0.6 millimeter roughness; Velostar 800 has 48 * 32 order number.

The result of described method for optimizing is as shown in table 1, and has provided the result of described not too preferable methods in table 2.In described table, the basic weight of " BW " expression paper show with every square metre gram numerical table, and the thickness of " thickness " expression single-part stationery is represented with thousand fens inches.In both cases, fast transfer all is to carry out after the more coarse fabric of described arrival, rather than ought transfer on the lower fabric of roughness and carry out.A kind of method of the value representation of being reported, wherein, described paper is transferred on a kind of coarse fabric fast, and in described method for optimizing, transfers to once more subsequently on the lower fabric of roughness.After above two transfer step, two kinds of paper are done end thoroughly, and reel, and do not roll.

Figure 7 illustrates MD and stretch and ABL factor data, second the quick transfer step that the figure shows after first quick transfer step makes described paper to obtain bigger intensity under the condition of specific CD amount of tension, and vice versa.For example, under 5% MD amount of tension, described preferred transfer method fast improves above 30% intensity.MD with appropriateness stretches and high-intensity paper is the good candidate of roller drying, makes that described paper can be unruffled or less-than-ideally have slightly wrinkling separating from described cylinder.Described improved intensity or stretching can be transformed into the improved flowability of paper machine and the improved physical characteristic of finished paper.

Table 1

% shifts fast	BW (gsm)	The thickness mil	MD Lalique/3 inch	%MD stretches	CD Lalique/3 inch	%CD stretches	ABL, km
								?0	?21．9	?11．7	?4010	?2．8	?1837	?1．8	?1．63
?10	?21．3	?15．4	?2473	?7．3	?1398	?2．4	?1．14
								?20	?23．9	?17．5	?1345	?12．9	?1144	?3．1	?0．68
?30	?23．7	?19．9	?1052	?21．1	?1060	?3．9	?0．58

Table 2

% shifts fast	BW (gsm)	The thickness mil	MD Lalique/3 inch	%MD stretches	CD Lalique/3 inch	%CD stretches	ABL, km
								30	?21．2	?32．8	?763	?20．7	?918	?8．9	?0．52
0	?23．0	?25．6	?3716	?1．8	?1473	?5．1	?1．32
								10	?23．8	?29．8	?1790	?5．4	?1214	?7．1	?0．81
20	?22．8	?30．5	?1140	?14．9	?1197	?8．3	?0．67
								30	?22．7	?31．4	?815	?19．6	?1076	?8．1	?0．54

Example 2

Paper with lamination hopper production stratiform, the ground floor of this paper has long fiber, the second layer has short crimped fibre, and the slurry (being lower than 0.6%) that described hopper will hang down denseness is deposited on the dapple fabric, and described fabric can produce the Mass Distribution of the variation of paper at formative stage.The described second layer contains 0.1% or higher release agent, and ground floor contains 0.1% or higher wet strengthening resin.With vacuum tank and paper tinsel described paper is dewatered to 18%-20% or higher denseness, shift fast with at least 10% acceleration amount then, preferred at least 25% acceleration is transferred on the dapple dry fabric of annular (the first transfer fabric or fabric roughness are approximately 1 millimeter fabric), as Lindsay Wire T-216-3 fabric.After shifting fast, paper is dewatered to about 30% or higher denseness, be dewatered to preferably approximately 36% or higher by the air press device, wherein, basically all air that applied all pass through described paper, and air pressure surpasses 30psi, preferably surpass 60psi, below described air press contact site, a vacuum tank is arranged, so that further bleed by described paper.Before described air press, described paper is carried out preheating with a steam chest, the paper of dapple quick operation is transferred on the more smooth fabric or felt then, the latter is dapple or has usually that to shift fabric than first low by at least 20%, preferred at least 50% or lower fabric roughness.Then described fabric is wound on gently on the Yankee surface at least 2 feet, preferably at least 7 feet, and apply enough pressure by fabric tension, so that described paper is fixed on Yankee, the pressure roll that described paper is connected on the Yankee applies the pressure that is lower than its wirking pressure 30% simultaneously, so that alleviate the compression of paper.At Yankee described paper is dried at least 70% denseness, further dry by another drum dryer then.Can carry out embossing to described paper and be used for commercial object with other conversion.Can carry out mould (pressure) system to described paper by air pressure difference, so that consistent with first and second any or two that shift in the fabrics.In addition, can adopt dapple pressure roll,,, perhaps keep the decorative pattern of fabric so that on described paper, produce extra decorative pattern as grooved roller.Described paper can be used as absorbed layer in bathroom tissue, face tissue, absorbability paper handkerchief, the absorbent article and part of disposable garment etc.

Above detailed description is used for illustration purpose.Therefore, under the prerequisite that does not break away from design of the present invention and scope, can carry out multiple improvement and change.For example, can be used as a kind of substituting or selectional feature formation another embodiment of built-up section disclosure of embodiment.In addition, there is the element of two titles can represent part with a kind of structure.In addition, can adopt various alternative methods and device structure, particularly shift and the dry improvement of carrying out at feedstock production, hopper, forming fabric, paper, perhaps disclosed in following document: in the application on the same day by the U.S. Patent application serial number (the unknown) of application such as M.Hermans, be entitled as " method that is used on improved conventional wet press, producing paper "; In with the application on the same day by the U.S. Patent application serial number (the unknown) of application such as M.Hermans, be entitled as " with put into production the method for low density paper of the energy of minimizing "; On the same day by the U.S. Patent application serial number (the unknown) of applications such as F.Chen, be entitled as " low density resilient webs and the method for producing this paper " in the application; U.S. Patent application serial number 08/912906 with equaled application on August 15th, 1997 by F.Chen is entitled as " wet elasticity paper and the disposable product made from this paper "; Above document is made this paper list of references by receipts.Therefore, the present invention is limited by disclosed specific embodiments, but limit by claims and equivalent thereof.

Claims (44)

1. A method of producing paper comprising: a) depositing an aqueous suspension of papermaking fibers on a forming fabric to form paper in a wet state; b) dewatering the wet paper to a consistency suitable for rapid transfer operations; c) rapidly transferring said dewatered paper onto a first transfer fabric having a three-dimensional shape; d) transferring said paper to a second transfer fabric; e) transferring the paper to the surface of a drum dryer; and f) separating the paper from the drum dryer surface. 2. A method of producing paper comprising: a) depositing an aqueous suspension of papermaking fibers on a forming fabric to form paper in a wet state; b) dewatering the wet paper to a consistency of about 20% or more; c) rapidly transferring said dewatered paper onto a first transfer fabric having a three-dimensional shape, the transfer fabric having a fabric roughness greater than the fabric roughness of said forming fabric; d) transferring said paper to a second transfer fabric having a lower fabric roughness than said first transfer fabric; e) transferring said paper from a second transfer fabric onto the surface of a tumble dryer and applying a pressure suitable to maintain a substantially three-dimensional shape on said paper; f) drying the paper; and g) separating the paper from the drum dryer surface. 3. 2. The method of claim 1 or 2, wherein said paper has a first surface which contacts said first transfer fabric during a flash transfer and subsequently contacts a surface of said tumble dryer. 4. The method of claim 3, further comprising an even number of additional transfers to other fabrics. 5. 2. The method of claim 1 or 2, wherein said first transfer fabric has a fabric roughness of 0.2-1.5 mm. 6. 2. The method of claim 1 or 2, wherein said first transfer fabric has a fabric roughness of 0.5 mm or greater. 7. 6. The method of claim 6, wherein said first transfer fabric has a fabric roughness of 0.5-1.2 mm. 8. 2. The method of claim 1, wherein the second transfer fabric has a lower fabric roughness than the first transfer fabric. 9. The method of claim 1 or 2, wherein the fabric roughness of the first transfer fabric is at least 3 times the fabric roughness of the forming fabric and at least 10 times greater than the fabric roughness of the second transfer fabric %. 10. 3. The method of claim 3, wherein the degree of rapid transfer is about 10% or greater. 11. 2. The method of claim 1 or 2, wherein said paper is separated from said drum dryer surface without creping. 12. A method as claimed in claim 1 or 2, wherein said paper is separated from said drum dryer surface by light creping. 13. 2. The method of claim 1, further comprising transferring said paper from the second transfer fabric back onto the first transfer fabric so that said paper is repositioned on the first transfer fabric. 14. 13. The method of claim 13 wherein said paper has a first surface which contacts said first transfer fabric during rapid transfer and an opposite second surface which subsequently contacts said tumble dryer. 15. 2. The method of claim 1 or 2, wherein said paper is dewatered to a consistency of about 25% or greater prior to transfer to said drum dryer surface. 16. 15. The method of claim 15, wherein said paper is dewatered to a consistency of about 30% or greater prior to transfer to said drum dryer surface. 17. 2. The method of claim 1 or 2, wherein said paper is non-compressively dewatered to a consistency of about 30% or greater prior to transfer to said drum dryer surface. 18. 17. The method of claim 17, wherein said paper is dewatered using an air compressor. 19. 17. The method of claim 17 wherein passing an air through said paper dewaters the paper prior to said paper contacting said drum dryer. 20. 2. The method of claim 1 or 2, further comprising wrapping a portion of said tumble dryer with a fabric to maintain good thermal contact between said tumble dryer surface and said paper. twenty one. 21. The method of claim 20, wherein said covering fabric is an elastic papermaking felt having a three-dimensional surface structure capable of pressing said paper against said drum dryer surface at varying pressures. twenty two. The method of claim 1 or 2, wherein the maximum pressure exerted on the paper at the point of maximum pressure when said paper is in contact with said second transfer fabric and with said tumble dryer surface is about 100 lbs/ linear inches or less. twenty three. 2. The method of claim 1 or 2, wherein said paper has a substantially uniform density and three-dimensional shape prior to placement on said drum dryer. twenty four. 23. The method of claim 23, wherein said dryer sheet has a substantially uniform density. 25． 2. The method of claim 1 or 2, wherein said dry paper has a bulk of about 6 cc/g or greater. 26． 25. The method of claim 25, wherein said dry paper has a bulk of about 9 cc/g or greater. 27． 2. The method of claim 1 or 2, wherein said papermaking fibers contain at least about 10% chemically hardened cellulosic fibers. 28． 2. The method of claim 1 or 2, wherein said papermaking fibers comprise about 10% high yield fibers. 29． 2. The method of claim 1 or 2, wherein said papermaking fibers contain at least about 20% recycled fibers. 30． 2. The method of claim 1 or 2, wherein said aqueous suspension contains an effective amount of a wet strength additive such that said dry paper has a wet:dry tensile strength ratio of at least 0.10. 31． A method according to claim 1 or 2, wherein said aqueous suspension contains a fiber release agent. 32． 2. The method of claim 1 or 2, wherein said tumble dryer has a machine speed of at least 1500 ft/min. 33． 32. The method of claim 32, wherein said tumble dryer has a machine speed of at least 2000 ft/min. 34． Soft paper produced by the method of claim 1. 35． Soft paper produced by the method of claim 2. 36． Soft, wrinkle-free paper produced by the method of claim 1. 37． 34. A paper produced by the method of claim 34, 35 or 36 having a surface thickness of at least 0.1 mm in the uncalendered state. 38． 37. Paper produced by the method of claim 37 having a surface thickness of at least 0.2 mm in the uncalendered state. 39． 37. Paper produced by the method of claim 37 having a surface thickness of at least 0.3 mm in the uncalendered state. 40． 34. A paper produced by the method of claim 34, 35 or 36 having an ABL of at least 0.2 km. 41． 36. Paper produced by the method of claim 34, 35 or 36 having a machine direction stretch of at least 6%. 42． 41. Paper produced by the method of claim 41 having a vertical stretch of at least 6%. 43． 3. The method of claim 1, 2 or 3, wherein said paper is dried using a non-rotary through-dryer. 44． 43. The method of claim 43, further comprising applying a release agent to the first transfer fabric after the first transfer and before transferring said paper back to the first transfer fabric.

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